Method of trimming rubber articles



"F.J. GLEASON. METHOD OF TRIMMING RUBBER ARTICLES. APPLICATION FILED APR23,I915.

1, 1 95,294. Patented Aug. 22, 1916.

" nl STATES PATE oir-FICE.

FREDERICK J.A GLEASO, 0F WALPOLE, MASSACHUSETTS, ASSIGNOR T0 STANDARD WOVEN FABRIC COMPANY, OF FRAMINGHAM, MASSACHUSETTS, A CORPQRATION' 0F MASSACHUSETTS.

METHOD orTRI1VI:MI1\IGv RUBBER ARTICLES.

Specification of Letters Patent.

Patented Aug'. 22, 1916,

Application led Apri123, 1915. Serial No. 23,491. v

To all 'whom it may concern:

Be it known that I, FREDERICK J. GLEA- at Walpole, in the county of Norfolk and 5 State of Massachusetts, have invented certain Improvements in Methods of Trlmming' Rubber Articles, of'which the followis left projecting from the perimeter of the article a thin fin of rubber constituting the D overiow from the molding operation. 1591s necessary to remove this lin in order to place the article in a salable condition, and this operation has usually been performed hereafter the article has been'removed from the mold. Inasmuch as rubber doesnot cut easily at ordinary temperatures this operation is arduous and relatively expensive.' ,g it is theA chief object of the present invention to devise a more expeditious method .'z of trimming articles of this character.

Referring now, to the accompanying drawings, Figure'l is a cross-sectional viewA 4 of a mold of the character used in the manufacture of rubber heels; Fig. 2 is a perspecl tive view of the middle section of the mold f l r on a shoe.. The knobs 14 are small enough 90 mn in Fig. 1; and Fig. 3 is a view simite Fig. 1 showing the manner in which s proposed to remove the nor othersur.- plus material from the heel.

rubber heels usually consist ofa top plate ection 6 which has an aperture formed. in'

The chargel of rubber .composition is, placed in this aperture and the upper plate or die pplied to vulcanize the stock. vA slightly actually necessary to make'the heel in order o be sure to have the mold well filledy This soN, a citizen of the United States, residing ing description, in connectionwith the ac ter are molded and vulcanized there usually tofore! by cutting off the n witha knifek tming operation. 1

' Any convenient The molds used in the manufacture of4 2, a bottom plate 4 and a middlevplate or t of the size and shape of the heel required.,-v

is forced downon the section 6of the mold ith great pressure, the'requiredheat being larger quantity of stock isI used than is of rubber articles. Y

i .-Having thus described my invention, what n,

cable'. to the manufacture of a great variety lis retained in the mold section 6 after the molding operation has been completed and whlle theparts are coolingod. Before the heel, has cooled suiiiciently to become'ela'stic the iin is cutaway, preferably bymeans of an abrading or buiiing tool 1'0. This operation should be performed while the rubber 1s 111 `the vbrittle or crumby condition [characteristic of this material at` certain tem- 70 peratures and in which condition 'it cuts very easily.- l,

, zThe.upper-.edge of-zthel section 6 of the mold serves as a guide or templet during the trimmingoperation, yand at the same time 75 this sectlonis partly cleaned by thetrimsansy maybe employedv to keep' the heel Ikfror'n, sticking to the upper plate 2- and `pulling out of theamold4 when 8c .this plate is removed, yA simple and convement means for effecting this object conrsists informing onlthe top-of each of the posts12, which projectv from the lower plate 4, a small knob 14. Thesep'osts support in 85 l the proper positions in the mold the washers 16 which'are to be embedded in the heel and they also form the holes throughwhich the fastenings will be driven-to secure the heel to pass freely .throughy the holes in the washers 16; but the rubber of the heel flows plate 14.. Any other `convenient means, however, may be employed 'for this purpose.

-After kthe trimming operation has been completed and the heel has cooled, the part Gis 100.

then pulled off thep'osts l2.' 'It 1s obvious that this method is appli-` separated from thebase 4 'and the-wheel is I claim as new and desire to secure by Letters Patent of the United States is 1. That improvement inthe method of shaping-rubber articles which consists in cutting away the surplus material while the article is hot enough to be'brittle.

2. That improvement in the method of trimming rubber articles which consists in cutting away the surplus material before.

the article has cooled, following the molding operation, suiliciently to become elastic.

3. That improvement in the method of shaping rubber articles which consists in removing the surplus material by abrasion `while the article is hot enough to be brittle.

4. That improvement in the method of trimming rubber articles which consists in cutting away the surplus material while the article is in the mold in which it has been vulcanized Aand before the article has cooled sufficiently to become elastic, and utilizing the mold as a Iguide for the cutting operation.

5. That improvement in the method of trimming rubber articles which consists in A holding the articlein a part of the mold in which it hasbeen vulcanized and which can be used yas `a templet, removing the surplus material by abrasionwhile so utilizing the mold and performing this operation While fthe rubber is hot enough to cut readily.

In testimony whereof I .have signed my name to this speciicationin the presence of the subscribing witness.

Witness:

MELROSE D. DAvms.

FREDERICK J. GLESON. 

